This invention relates to phenols alkylated with high molecular weight terpolymers and to the preparation of such alkylated phenols. More particularly this invention relates to phenols alkylated with ethylene-propylene-diene terpolymers which are novel and useful intermediates for the preparation of multifunctional additives for lubricating oils.
The alkylation of phenol with low molecular weight polymers, particularly with homopolymers of C.sub.3 - C.sub.5 olefins, is well known in the art. For example, U.S. Pat. No. 2,398,253 discloses alkylation of phenol with C.sub.8 - C.sub.12 polymers of n-butene in the presence of BF.sub.3 catalyst, with short reaction time, and at a reaction temperature not exceeding about 160.degree. F. The patent further teaches that use of high temperatures, long contact times, and more than equal molar proportions of phenol lead to formation of low molecular weight products and/or dialkyl phenols.
U.S. Pat. No. 2,655,544 discloses the alkylation of phenol with propylene polymer at about 85.degree. to 125.degree. F with 3% BF.sub.3 as catalyst to obtain a yield of about 85% of alkyl phenol having about 21 carbon atoms in the alkyl group. Use of polymers of isobutylene in the alkylation, for example tetraisobutylene, resulted in fragmentation of the polymer, and the princial product obtained was octyl-phenol rather than the expected C.sub.16 alkyl phenol.
British Pat. No. 1,159,368 discloses the alkylation of phenol with C.sub.50 and higher polymers and copolymers of propylene and butylene in the presence of BF.sub.3 catalyst and at a temperature below about 150.degree. F. Yields of alkylated phenol, based on polymer, care substantially below 100% because the double bond required for the alkylation reaction is present in about only 75% of the polymer molecules. In addition, polymer fragmentation during reaction is a problem and is controlled, but not eliminated, by conducting the reaction at temperatures preferably not above about 120.degree. F.